1. Field of the Invention
The present invention relates to a pin type transfer apparatus for apertured-workpieces, comprising a transfer chain adapted to circulate in an endless form inside a conveyor frame along a lateral surface thereof, and workpiece transfer pins fixed to said transfer chain, said transfer chain and pins constituting a main line. More particularly, a transfer chain is provided which travels in an endless circulating form inside a conveyor frame along a lateral plane thereof and pins are fixed to said chain at predetermined equal or unequal intervals and horizontally project beyond the conveyor frame so that workpieces can be freely received by and removed from the revolving workpiece transfer pins. Inlet means and outlet means according to the present invention are provided with the ability to identify the type of workpieces in connection with the workpiece transfer pins, so that the function as a transfer apparatus is enhanced, thus providing for the storage of workpieces between work stations in addition to the mere interconnection of work stations.
2. Description of the Prior Art
Several forms of pin type transfer apparatus comprising a chain adapted to circulate in an endless form and pins attached to said chain and adapted to catch workpieces have already been known. These conventional forms, however, transfer workpieces simply from below to above or in one direction alone. In recent years, manufacturers and other persons in the industry have come to give serious attention to the increasing needs for complete automation of production processes, lavor saving and effective use of land and buildings. In the field of the pin type transfer apparatus, researches have been conducted and drawbacks of the conventional forms have been detected. The conventional pin type transfer apparatuses, particularly those having a vertical transfer portion and a horizontal transfer portion have been found to have the following problematic points.
First of all, in the conventional pin type transfer apparatus, particularly when it has a horizontal transfer portion, transfer by the return side of the chain in the horizontal transfer portion is impossible. Second, when the direction of transfer of workpieces is turned downwardly from the horizontal transfer portion, the workpiece becomes unstable and a fall-preventive plate or the like is required. Further, it is necessary to adjust the clearance between such fall-preventive plate and the frame to the width dimension of the workpiece. Third, because of the restriction placed on the direction in which the pins are attached, it is difficult to turn the direction of transfer of workpieces since workpieces interfere with the sprockets. Fourth, the components in the workpiece reception and delivery sections must be grooved and it is necessary to adjust the width of the grooves in accordance with changes in the width dimension of workpieces.